Track the active ExtensionKeybindingRegistry and make it available to EventRewriter.

chrome/browser/ui/browser_window.h

Index: chrome/browser/ui/browser_window.h
diff --git a/chrome/browser/ui/browser_window.h b/chrome/browser/ui/browser_window.h
index 880f6e8adf69af76bec3fa32f86c0ddd61b4a09d..801e6e5f7a6600db9390fa2ac0264a74e5687f4a 100644
--- a/chrome/browser/ui/browser_window.h
+++ b/chrome/browser/ui/browser_window.h
@@ -16,6 +16,7 @@
 #include "chrome/browser/ui/sync/one_click_signin_sync_starter.h"
 #include "components/content_settings/core/common/content_settings_types.h"
 #include "components/translate/core/common/translate_errors.h"
+#include "ui/base/accelerators/accelerator.h"
 #include "ui/base/base_window.h"
 #include "ui/base/window_open_disposition.h"
 #include "ui/gfx/native_widget_types.h"
@@ -402,6 +403,10 @@ class BrowserWindow : public ui::BaseWindow {
   virtual void ExecuteExtensionCommand(const extensions::Extension* extension,
                                        const extensions::Command& command) = 0;
 
+  // Returns whether the given |accelerator| is registered by an extension.
+  virtual bool IsExtensionCommandRegistered(

[sky, 2014/09/10 23:55:14]

This feels like something profile specific, and not per browser window. It seems
like you've wired it this way as ExtensionKeybindingRegistry is created per
window. Is there some other way to get this information through the profile?

[David Tseng, 2014/09/11 00:05:25]

In the case of global commands, the registry is associated with a profile.
Unfortunately, the non-global registry lives in a window, so I don't think
there's any other way to get at the owner (BrowserView -> ToolbarView ->
BrowserActionsContainer). If there's some other way of getting a
BrowserActionsContainer based on a profile or BrowserContext, I'd be happy to do
that, but I don't think that's available.

 @finnur, why was the non-global registry placed in BrowserActionsContainer?

[Finnur, 2014/09/11 09:51:58]

It has been quite a while, but as I recall it is because it has the same
lifetime as the BrowserActionsContainer, is conceptually related to it (the BAC
shows extensions and the Registry is handling shortcuts for them). And it also
needs access to the focus manager for that window in order to register
accelerators.

I do have an urge to loop in Devlin, though, as he's been revamping this area
and may have good ideas.

+      const ui::Accelerator& accelerator) = 0;
+
  protected:
   friend class BrowserCloseManager;
   friend class BrowserView;